The impact of the COVID-19 pandemic on the global burden of mental disorders: a counterfactual modeling study from 1990 to 2021

The COVID-19 pandemic has intensified the global burden of mental disorders, yet the gap between observed and counterfactual burdens without the pandemic, especially for major depressive and anxiety disorders, remains unexplored. To assess this gap, including its impact on specific regions and populations, thereby guiding future mental health services and policy development. Data of age-standardized prevalence rate (ASPR), age-standardized incidence rate (ASIR) and age-standardized disability-adjusted life years rate (ASDR) for mental disorders from 1990 to 2021 were extracted from the Global Burden of Disease dataset. This study employed a counterfactual model that combines Autoregressive Integrated Moving Average and Long Short-Term Memory to assess the impact of the COVID-19 pandemic on the global burden of mental disorders by quantifying the difference between actual and predicted rates. In 2021, mental disorders were more prevalent in higher Social Development Index (SDI) regions such as the North Americas, and European region. During the COVID-19 pandemic (2020-2021), these regions, including countries like Denmark and the United States, saw significant increases in the ASPR, ASIR and ASDR of mental disorders, far exceeding predictions. Globally, the ASIR for men increased from a predicted 3917 to an observed 4435 per 100,000, while for women, it rose from a predicted 5497 to an observed 6382 per 100,000. Specific disorders like major depressive disorder and anxiety disorders showed even larger discrepancies, with ASPR of anxiety disorders exceeding predictions by 1135 and 1043 per 100,000 in Bolivia and Peru, respectively, and ASIR of major depressive disorder in Greenland surpassing predictions by 1156 per 100,000. The pandemic also had a significant impact on mental health across different age groups, with individuals aged 15-40 years experiencing the greatest increase in anxiety and major depressive disorders, particularly among women. In conclusion, during the COVID-19 pandemic, the global burden of mental disorders far exceeded the counterfactual predictions, with major depressive and anxiety disorders showing the largest increases. This underscores the pandemic's severe impact on mental health and the urgent need for enhanced global mental health services, including ongoing evaluation and support.